• Proceedings of the Korea Air Pollution Research Association Conference
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• 1998.10a
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• pp.261-262
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• 1998

1970년대 미국에서는 MTBE를 휘발유 첨가제로서 사용하여 자동차 배기가스에 의한 대기오염문제를 해결하려고 헨다. 현재 우리나라에서도 정유사에서 MTBE가 첨가된 휘발유의 공급을 증가시키면서 이의 사용량 역시 늘어나는 추세이다. 그러나 최근 ArIBE의 사용에 따른 새로운 종류의 대기오염에 대만 우려가 대두되고 있는데 이는 대기중 방출된 MTBE가 대기중에 존재하는 여러 분자체 및 라디칼등과 반응하여 인체에 유독한 물질들을 생성할 수 있는 것이 밝혀지고 있기 때문이다 따라서 이러한 새로운 사실얘 대한 위해도평가가 이루어지기 위해서는 무엇보다도 이 물질의 대기 중에서의 거동에 대한 이해가 우선되어야 할 것이다.

• Journal of Digital Convergence
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• v.14 no.10
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• pp.71-81
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• 2016

The objective of this study is to suggest methods to improve in-home service quality through service evaluation by long-term care workers. To achieve this objective, general characteristics of 223 long-term care workers, evaluation of service and agency, and retraining needs have been surveyed. An assessment of the survey results have resulted in the following conclusions. Though long-term care workers are not uneducated, the majority face unstable employment. And the content of supervision hoped for in producing improved long-term care services has been found to be based on the service-user's relationships. Moreover, among topics needing to be addressed for retraining, much attention has been shown for understanding of the elderly and their families, health care knowledge about geriatric diseases, and counseling techniques directed towards the affected person and their family. Findings from the research are as follow: enhancing the quality of long-term care requires a structural reassessment; upgrading the quality of care agencies requires the improvement of methods used to raise awareness of users and their guardians and the expansion of opportunities for education programs for professionalism.

• Membrane Journal
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• v.23 no.2
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• pp.170-175
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• 2013

Poly (vinyl alcohol) (PVA) solution containing the glutaraldehyde (GA) as a crosslinking agent was coated onto the polyacrylonitrile (PAN) hollow fiber membrane as the supporter. Pervaporation experiments were carried out to characterize the prepared PVA/PAN composite membrane for water-isopropyl alcohol mixture. The flux and separation factor were measured at 30, 50, $90^{\circ}C$ for the feed mixture of aqueous 85 wt% IPA solution with varying the reaction temperature and composition of coating solutions. Typically the flux showed 1,870 $g/m^2{\cdot}hr$ at $90^{\circ}C$ feed mixture and the coating concentration of 3.5 wt% and the highest separation factor of 804 was obtained at $30^{\circ}C$ feed mixture and the coating concentration of 7 wt% as well.

• Convergence Security Journal
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• v.22 no.5
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• pp.49-59
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• 2022

Cyber security in the automobile sector is a key factor in the life cycle of automobiles, and cyber security evaluation standards are being strengthened worldwide. In addition, not only manufacturers who design and produce automobiles, but also due to the nature of automobiles consisting of complex components and various parts, the safety of cybersecurity can be secured only when the implementation level of the cybersecurity management system of companies participating in the entire supply chain is evaluated and managed. In this study, I analyzed the requirements of ISO/SAE 21434 and TISAX, which are representative standards for evaluating automotive cybersecurity. Through a survey conducted on domestic/overseas company security officers and related experts, suitability and feasibility were reviewed according to priorities and industries, so 6 areas and 45 evaluation criteria were derived and presented as final evaluation items. This study is meaningful as a study in that it presented a model that allows companies participating in the automotive supply chain to evaluate the current cybersecurity management level of the company by first applying ISO/SAE 21434 and TISAX overall control processes before uniformly introducing them.

• Membrane Journal
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• v.23 no.2
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• pp.129-135
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• 2013

To recover of volatile organic compounds (VOCs) induced by painting process, we prepared separation system using hollow fiber membrane modules and evaluated the recovery performance of VOCs with different feed pressure and operating time. Concentration of volatile organic compound in permeate through the membrane increased with increasing operating time and pressure. Performance of the membrane for removing the VOCs when we applied 2-stage process showed better performance than that of single stage process.

• Journal of Environmental Health Sciences
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• v.33 no.2 s.95
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• pp.158-165
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• 2007

본 연구는 근원에 따른 용존 유기물의 특성을 평가하기 위해 하천수, 호소수, 하수 2차 처리 유출수의 자연수 및 Aldrich, Wako 사에서 공급된 휴믹산을 대상으로 분자량 분포에 따른 물리 화학적인 수질 특성, 생분해도, 소독, 부산물의 생성 등을 고찰하였다. SUVA를 이용해서 자연수의 생분해 가능성을 평가한 결과 호소수, 하수, 하천수 순으로 예측되었으며 이는, 실제 생분해도 실험 결과와 유사하였다 생분해 반응 중 저분자 영역대의 용존 유기물은 점차 감소하였고 반면에 고분자 영역대의 용존 유기물은 증가하였다. SMP는 전체 용존 유기물의 0.7-5.5%정도 관찰되었으며 고분자 물질을 많이 함유한 시료에서 높게 나타났다. THM 생성은 대체로 고분자 물질이 높을수록 증가하였으며 THMFP도 Wako 휴믹산을 제외한 샘플에서 이와 유사한 경향을 나타냈다.

• 월간 기계설비
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• no.10 s.195
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• pp.63-67
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• 2006

1973년 창업한 (주)대우건설은 IMF 이후 지난 2000년 그룹 해체와 WORKOUT에 들어가는 어려움을 겪었다. 그러나 전 임직원이 일심단결 해서 어려움을 슬기롭게 극복하여 2005년에는 수주 8조, 1,900억원, 매출 5조 756억원, 영업이익 4,315억원으로 업계최고의 실적을 올렸다. 또한 최근 발표한 2006년 시공능력평가에서 드디어 1위로 등극해 명실상부한 최고의 건설사로 올라서는 쾌거를 달성했다. (주)대우건설은 건축, 주택, 토목, 플랜트, 해외사업 등 건설 전 분야에서 업계최고의 실적을 유지하고 있다. 특히 주택 분야에서는 푸르지오의 브랜드를 앞세워 5년 연속 주택 공급 1위의 실적을 자랑하고 있다. 2006년 (주)대우건설은 업계최고의 기술력과 영업경쟁력, 우량재무구조를 바탕으로 수주8조 5,000천억 매출 5조 5,826억원의 경영목표를 세웠으며, 이를 위해 전 임직원이 「도전과 열정」, 「자율과 책임」의 핵심 가치를 바탕으로 오늘도 매진하고 있다.

• Journal of Korea Water Resources Association
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• v.39 no.12 s.173
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• pp.1057-1066
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• 2006

Water is an indispensable input to human's existence and industrial production. A water supply project would demand considerable costs, but produce economic benefits, which are importantly utilized in the project evaluation. In this situation, this study attempts to value the economic benefits from the residential water supply in Seoul. In particular, yearly consumer surplus and economic value of water supply for eleven water authority agencies in Seoul are measured during the period 2001-2004. Information on price elasticity required in calculating consumer surplus is obtained from direct estimation of the residential water demand function, and the consumer surplus is assessed by using a recently developed formula. Price elasticities used here are -0.810 and -1.011, and the estimated consumer surplus and economic value amount to 131.9 to 164.6 billion won and 398.6 to 431.3 billion won, respectively.

• Membrane Journal
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• v.23 no.5
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• pp.360-366
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• 2013

The Poly (vinylidene fluoride) and poly (acrylonitrile) (PAN) hollow fiber composite membranes coated with poly (vinyl alcohol) (PVA) and poly (acrylic acid) (PAA) as the crosslinkig agent are prepared. The resulting membranes were characterized for aqueous 90 wt% ethanol solution by pervaporation techniques in terms of the permeability and separation factor. In general, as both the crsslinking reaction temperature and the crosslinking agent concentration increase, the permeability decrease while the separation factor tends to increase. And also the permeability increased and the separation factor decreased as the feed temperature increased. Typically, the permeability $502g/m^2hr$ at the feed temperature $70^{\circ}C$ was obtained for PVDF hollow fiber membrane prepared with the crosslinking agent PAA 3 wt% at the reaction temperature $60^{\circ}C$ whereas the separation factor 218 was shown for the membrane reacted with PAA 11 wt% and at $100^{\circ}C$ for the feed temperature $50^{\circ}C$.

• Journal of IKEEE
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• v.16 no.1
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• pp.1-6
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• 2012

Thermal rating or lifetime evaluation for aged overhead transmission line becomes more important concerns with respect to keeping power delivery stable having proper capability. Both load rating and dip/clearance are essential factors to determine transmission capacity. In order to evaluate thermal rating and conductor lifetime for domestic transmission lines with double-circuit, the dip/ground clearance standards as well as the electrical equipment technical standard are examined. Conductor temperature and dip are calculated under the assumption of a contingency, and then, a method to up-rate load capacity is searched. As thermal rating and limit dip for aged conductor are properly evaluated, an improved strategy in order to guarantee the existing power system reliability is presented in this paper.